CN101261235A - Crude oil gas fraction and moisture percentage dual energy x ray measurement method - Google Patents

Abstract

The invention relates to a dual energy x ray measuring method for gas ratio and water ratio in crude oil. The method uses the x ray produced by an x light machine together with the principle of material interaction to measure the indexes of gas ratio and water ratio in oil pipelines under the condition of a three-phase medium, such as oil, water and gas in oilfield production. The detection method, which relies on measuring equipment consisting of three big subsystems as well as a set of special software, consists of a subsystem of producing dual energy x ray, a detector subsystem consisting of one or two detectors, a general control and data processing subsystem, and a collimator as well, wherein, the special software adopts a special algorithm to solve the water ratio Omega 1 and gas ratio Omega 3. The method establishes a theoretical model with high accuracy, wherein, physical significance of various parameters is comparably clear. The method has the advantage of simple use and considers factors such as temperature, pressure, etc. The system also overcomes the severe hidden safety trouble caused by a radioactive source and is particularly suitable for the measuring system of automatic online in oilfield production.

Description

The dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil

Technical field

The present invention relates to the oil field of measuring technique, be specifically related to the measuring system of crude oil gassiness water percentage, be specifically related to χ ray and material action principle that a kind of χ of utilization ray machine produces, in the field produces, measure the dual intensity χ radionetric survey technology of water percentage and void fraction index in the oil pipeline under profit gas three-phase medium and the condition of depositing, belong to International Classification of Patents G01N technical field.

Background technology

Crude oil from the crude oil that oil mining goes out, is the potpourri that multiphase mediums such as oil, water, rock gas are formed as one of most important energy.Handle this potpourri and at first will carry out gas-liquid separation, remaining oil-water mixture body obtains the very low product oil of water percentage after processed defeated or sell outside carrying out.In a series of activities in production such as dehydration of crude oil processing, need grasp situations such as crude oil water content and void fraction timely and accurately, so that the control production run guarantees to produce qualified finished product crude oil.Therefore, index such as crude oil water content and void fraction is important parameter in petrochemical industry petroleum collection, smelting and the transportation.Particularly many maturing fields, the main at present water flood recovery technology that adopts, the water percentage of extraction crude oil is generally higher.Therefore, the accurate detection that crude oil is carried out water percentage and void fraction has vital role in crude production, trade.

Measure crude oil water content at present and mainly contain following several method: manually distill assay method, microwave method (or radio frequency method), capacitance method, shortwave method, heat conduction method, vibration densimeter method and gamma-rays method.1, microwave method (as CN1112677) is to interact according to electromagnetic wave and dielectric material, its dissipation is relevant with the size and the relative dielectric constant of material, the different radio-frequency (RF) impedance characteristic differences that cause measurand to present of oil with the specific inductive capacity of water, when radiofrequency signal passes to the oil water mixture when being the condenser type radio frequency sensor of medium, its loaded impedance changes along with the different ow ratios of blending agent, promptly when crude oil water content changed, wave parameter changed thereupon, thereby realized measurement of water ratio; 2, capacitance method (as: CN1186236) is the specific inductive capacity difference according to profit, is reflected to the electric capacity difference of the capacitor that is made of pole plate, measures the variation of electric capacity, the variation that just can measure water percentage; 3, shortwave method (as: CN2349574) is to utilize the short-wave signal of one (back) probe emission 3.579MHz in crude oil, current crude state is investigated thoroughly, at interval after several seconds, at short-wave signal by another (preceding) probe emission 3.579MHz in crude oil, take out the signal of Water in oil again, get the difference that secondary records then, can draw instantaneous water percentage after treatment; 4, heat conduction method (as: CN1259671) is utilized the difference of the thermophysical property of liquid-gas-liquid two-phase liquid, as heat conduction, specific heat, viscosity etc., measures the water percentage and the profit flow of crude oil simultaneously; 5, vibration densimeter method (as: CN1789969, CN2359692) utilize the level gauging element to measure the liquid level of the interior crude oil of storage tank (or separation vessel), pressure measuring instruments is measured the pressure of no crude oil part in the storage tank (or separation vessel) and the pressure that bear the bottom, calculates by experimental formula at last; 6, (as: CN1086602A is when passing different medium according to gamma-rays CN2383068Y) to rays method for CN86105543A, CN2359692Y, the principle work that its decay is different.The various measuring methods of except that the gamma-rays method other, all belong to contact type measurement, because crude oil corrosivity is stronger, fouling, wax deposition are serious, cause the poor reliability of instrument long-time running, especially these instrument all can't be eliminated the influence that gassiness brings measurement of water ratio, and have caused bigger measuring error.To this, patent CN2452022Y, CN2646704Y with the CN2646705Y specialized designs different erasers come the impurity of sensor outside accumulation.In addition, the water percentage that capacitance method, radio frequency method and microwave method are measured change and measured between be nonlinear relationship, in a certain water percentage scope, flex point is arranged, and crude oil is profit gas mixture, its physicochemical property are changeable, so the top several measuring methods except that the gamma-rays method in actual applications, all can not satisfy production requirement well.

The water in oil analyzer of working according to gamma-rays and matter interaction rule and the macroscopical fluidised form and the chemical property of fluid-mixing are irrelevant, can carry out the measurement of water percentage and void fraction to the crude oil of complexity, are subjected to the welcome in oil field deeply.

Patent of invention CN86105543A disclose a kind of utilize radioactive source (as ¹⁰⁹Cd, or ²⁴³Am etc.) monoenergetic gamma rays that sends is to the measuring principle of the volumetric water content of two-phase profit mixture.Utility model patent CN2359692Y has announced a kind of utilization ²³⁸The device that the Pu radioactive source is measured the water percentage of two-phase profit mixture.Patent of invention CN1086602A discloses a kind of in three-phase profit gas mixture, measures the automatic measuring instrument of gassiness, water percentage in the crude oil; Be fixed with gamma ray projector and transmission detectors respectively in radial center line symmetry both sides, the sidewall upper edge of measuring channel; Becoming angle with transmission detectors place center line and axially on the center line sidewall of certain distance, be fixed with scattering detector with it with gamma ray projector along measuring channel; According to the result who measures, obtain gas volume fraction and volumetric water content at last through data processing.Document [1] has been done further discussion to its measuring principle from theory.Utility model patent CN2383068Y is to the device according to above-mentioned principle design, improve, increased a stirring apparatus, the profit gas that comes out in the oil well is mixed, so that further satisfy the theory hypothesis condition, so that improve the precision of measuring.In any case, this theoretical model is got approximate place too much, and each parameter physical significance is indeterminate, to the influence of running parameters such as pressure, temperature, considers to revise, and these have finally still influenced the method and the measuring accuracy of its use.

In addition, the gamma-ray measurement method of using radioactive source to produce also has a bigger weakness, has the radiological safety problem exactly, and particularly in anti-terrorism situation at present relatively severeer period, this weakness is more outstanding.

Find to use dual intensity χ rays method in the market as yet and measure the principle and the device of void fraction and water percentage in the crude oil.

Summary of the invention

Purpose of the present invention is in the three-phase Oil, Water, Gas mixture, and real-time high-precision is measured the demand of gassiness, water percentage in the crude oil, and a kind of principle and method that adopts dual intensity commercial measurement gassiness, water percentage is provided.

The objective of the invention is to be achieved through the following technical solutions.

The dual intensity χ radionetric survey method of void fraction and water percentage in a kind of crude oil is χ ray and a material action principle of utilizing the χ ray machine to produce, in field produces, and under the profit gas three-phase medium and the condition of depositing, water percentage and void fraction index in the measurement oil pipeline.This measuring method relies on a measuring equipment and a cover special software of mainly being made up of three big subsystems, that is: the generation subsystem of two kinds of energy χ rays, the detector subsystem that one or two cover detectors constitute, and master control and data processing subsystem are formed; Other device also comprises collimating apparatus; Described detector subsystem comprises unit such as detector, prime amplifier or photomultiplier, signal shaping, amplification, sampling maintenance, AD conversion; Total control and data processing subsystem comprise the transmission of data, synchronously, parts such as demonstration, control and warning; Adopted special algorithm to find the solution water percentage ω in the described special software ₁With void fraction ω ₃ω ₁The shared percentage by weight of expression water is a water percentage, ω ₃The shared percentage by weight of expression rock gas is a void fraction, ω ₂The percentage by weight ω that expression oil is shared ₂=1-ω ₁-ω ₃

Under profit gas three-phase state, this software has adopted two following equations to find the solution water percentage ω ₁With void fraction ω ₃,

$({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1\left(E_H^{*}\right)}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})+{\mathrm{\ω}}_3(\frac{{\mathrm{\μ}}_3\left(E_H^{*}\right)}{{\mathrm{\ρ}}_3}-\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)$

$=\ln \left(\frac{k_H{N}_0\left(E_H^{*}\right)}{N(x,E_H^{*})-k_H{c}_H{N}_0\left(E_H^{*}\right)}\right)---\left(13\right)$

$({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1\left(E_L^{*}\right)}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})+{\mathrm{\ω}}_3(\frac{{\mathrm{\μ}}_3\left(E_L^{*}\right)}{{\mathrm{\ρ}}_3}-\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)$

$=\ln \left(\frac{k_L{N}_0\left(E_L^{*}\right)}{N(x,E_L^{*})-k_L{c}_L{N}_0\left(E_L^{*}\right)}\right)---\left(14\right)$

In the above-mentioned equation: E _H ^*, E _L ^*Represent the high energy and the pairing equivalent energy of low energy χ ray of χ ray machine respectively; ρ represents the actual density under the profit gas three-phase state in the oil pipe, ρ ₁Represent in the actual oil pipe density of pure water under the conditions such as pairing temperature, pressure, ρ ₂Represent in the actual oil pipe density of pure crude oil under the conditions such as pairing temperature, pressure, ρ ₃Represent in the actual oil pipe density of pure natural gas under the conditions such as pairing temperature, pressure; μ ₁, μ ₂, μ ₃Represent pure water, pure crude oil, the linear attenuation coefficient of pure natural gas under the equivalent ray energy of correspondence respectively; X represents in the oil pipe, the linear thickness of test macro measurement space; N ₀(E ^*) representative under the equivalent ray energy condition of correspondence, when existing without any material in the oil pipe, the counting that test macro is measured; N ₀(x, E ^*) represent under the measurement thickness of correspondence, equivalent ray energy condition the counting that test macro is measured; K, c are respectively correction factor, same μ ₁, μ ₂, μ ₃Together, can try to achieve by measuring exponential decay curve in advance.

When only considering profit two-phase state, can be reduced to monoenergetic to the χ ray machine energy of measuring system, adopted following formula to find the solution water percentage ω in the at this moment described software ₁,

${\mathrm{\ω}}_1=\frac{\ln \left(\frac{k{N}_0}{N\left(x\right)-\mathrm{kc}{N}_0}\right)-\left(\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2}\right)\mathrm{x\ρ}}{(\frac{{\mathrm{\μ}}_1}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})\mathrm{x\ρ}}---\left(9\right)$

In the formula: ρ represents the actual density under the profit two-phase state in the oil pipe, ρ ₁Represent in the actual oil pipe density of pure water under the conditions such as pairing temperature, pressure, ρ ₂Represent in the actual oil pipe density of pure crude oil under the conditions such as pairing temperature, pressure; μ ₁, μ ₂Represent pure water, the linear attenuation coefficient of pure crude oil under the equivalent ray energy of correspondence respectively; X represents in the oil pipe, the linear thickness of test macro measurement space; N ₀Representative under the equivalent ray energy condition of correspondence, when existing without any material in the oil pipe, the counting that test macro is measured; N ₀(x) represent under the measurement thickness of correspondence, equivalent ray energy condition the counting that test macro is measured; K, c are respectively correction factor, same μ ₁, μ ₂Together, can try to achieve by measuring exponential decay curve in advance.

During design χ optical-mechanical system, the certain condition that satisfies between the high and low energy is taken into account high energy E _H ^*With low energy E _L ^*Difference big more, measuring accuracy is high more; For example: $E_H^{*}\≈(1.5~3)E_L^{*},$ More simply, $E_H^{*}={2E}_L^{*};$ The energy range of described high energy χ ray machine can be taken between 10keV～1MeV.

This measuring method relies on true dual intensity χ ray machine measuring system, the mounting means of its measuring equipment core component, be to produce subsystem at the horizontal diameter one end installing χ of crude oil pipeline ray, comprise true dual intensity χ ray machine control system, connect collimating apparatus and collimating apparatus, be provided with the target spot of the high energy χ ray that the position overlaps substantially and the target spot of low energy χ ray in the collimating apparatus screened room; The other end installing detector subsystem of crude oil pipeline horizontal diameter, comprise detector and shielded-plate tube, connect master control and data processing subsystem, comprise high-voltage power supply, first via AD converting unit, first via control module and the data handling machine of interconnective first via signal shaping, amplification and sample holding unit, first group of detector.

This measuring method relies on two monoenergetic χ ray machines and produces high low energy χ ray, the mounting means of its measuring equipment core component, be by the control system of the high energy χ ray machine of parallel arranged and the control system of low energy χ ray machine, the target spot and high energy χ ray machine collimating apparatus and the screened room that connect high energy χ ray machine respectively, and the collimating apparatus and the screened room of low energy χ ray machine target spot and low energy χ ray machine, described two monoenergetic χ ray machines, corresponding two groups of detector subsystems respectively---first group of detector and shielded-plate tube, second group of detector and shielded-plate tube, form two parallel detections along separate routes, two groups of detector subsystems connect master control and data processing subsystem separately respectively, that is: one group connects first via signal shaping, amplify and sample holding unit, the high-voltage power supply of first group of detector, first via AD converting unit, first via control module, another group connects the second road signal shaping, amplify and sample holding unit, the high-voltage power supply of second group of detector, the second road AD converting unit, the second road control module; Two groups of data reach data handling machine respectively.

This measuring method relies on pseudo-dual intensity χ ray machine measuring system, the mounting means of its measuring equipment core component, comprise a monoenergetic χ ray machine control system, corresponding rotation mechanism, power spectrum pre-hardening device is installed together with rotating mechanism, the outer cover collimating apparatus, corresponding with it first group of detector and the shielded-plate tube installed; The target spot of χ ray machine, collimating apparatus, detector and shielded-plate tube are formed a cover χ X-ray detection X path, connect high-voltage power supply, first via AD converting unit, first via control module and the data handling machine of first via signal shaping, amplification and sample holding unit, first group of detector.

This measuring method relies on two monoenergetic χ ray machine measuring systems, the mounting means of its measuring equipment core component, adopted the horizontal mounting means of two monoenergetic χ ray machines and detector, be to install at four end points positions up and down of crude oil pipeline, load the control system of high energy χ ray machine and the control system of low energy χ ray machine respectively at its left end and lower end, be combined with the target spot of high energy χ ray machine respectively, the collimating apparatus and the screened room of high energy χ ray machine, and the collimating apparatus and the screened room of the target spot of low energy χ ray machine and low energy χ ray machine, the target spot of high energy χ ray machine, collimating apparatus, form a cover high energy χ X-ray detection X path, the target spot of low energy χ ray machine with detector and shielded-plate tube that the crude oil pipeline right-hand member is installed, detector that collimating apparatus and crude oil pipeline right-hand member are installed and shielded-plate tube are formed a cover low energy χ X-ray detection X path; Two covers are surveyed path and are on the same xsect of crude oil pipeline, to reduce the length of measuring equipment; The angles that two covers are surveyed paths can change, and perfect condition is, angle is the smaller the better, and when homogeneity was relatively good on the crude oil pipeline xsect, its angle can be greatly.

This measuring method relies on pseudo-dual intensity detector, and the mounting means of its measuring equipment core component comprises a monoenergetic χ ray machine control system, outer cover collimating apparatus, the corresponding with it power spectrum filter of installing in the detector front, first group of detector and shielded-plate tube; The target spot of χ ray machine, collimating apparatus, power spectrum filter, detector and shielded-plate tube are formed a cover high energy χ X-ray detection X path, connect high-voltage power supply, first via AD converting unit, first via control module and the data handling machine of first via signal shaping, amplification and sample holding unit, first group of detector.The shielded-plate tube of target spot, collimating apparatus, second group of detector and second group of detector of χ ray machine is formed a cover low energy χ X-ray detection X path simultaneously, connects high-voltage power supply, the second road AD converting unit, the second road control module and the data handling machine of the second road signal shaping, amplification and sample holding unit, second group of detector

If the line less stable of χ ray machine in order to improve measuring accuracy, can add one road gamma correction detector.It is characterized in that: the outlet of each χ ray machine install one road gamma correction detector or; The gamma correction position of detector flows but had better not block the main beam that is used to measure in the outlet of χ ray machine.With the gamma correction detector is that example illustrates its installation relation: the target spot of χ ray machine, collimating apparatus and gamma correction detector are formed a cover χ ray line size detection path, connect high-voltage power supply, Third Road AD converting unit, Third Road control module and the computing machine of Third Road signal shaping, amplification and sample holding unit, Third Road detector.

Dual intensity χ radionetric survey technology of the present invention, χ ray and the material action principle of promptly utilizing the χ ray machine to produce, in field produces, under the profit gas three-phase medium and the condition of depositing, water percentage and void fraction index in the measurement oil pipeline.This system has overcome the major safety risks that radioactive source brings, and is specially adapted in the field produces automatic on-line metering system.The ratio of precision of theoretical model of the present invention is higher, and the physical significance of various parameters is clearer and more definite, uses simply, can also consider the influence of factors such as temperature, pressure, is specially adapted in the field produces automatic on-line metering system.When utilizing X-ray machine as radiographic source, can exempt the puzzlement of losing radioactive source, improved radiation proof safety coefficient, fundamentally stopped the chance that the terrorist obtains the dirty bomb raw material, national security there is the meaning of particular importance.

Description of drawings

Fig. 1-1 is the energy spectrogram of 20keV molybdenum target χ ray machine;

Fig. 1-2 is the energy spectrogram of 30keV molybdenum target χ ray machine;

Fig. 1-3 is the energy spectrogram of 35keV molybdenum target χ ray machine;

Fig. 1-4 is the energy spectrogram of 50keV molybdenum target χ ray machine;

Fig. 2 is true dual intensity χ ray machine and detector mounting means synoptic diagram;

Fig. 3 is two monoenergetic χ ray machines and the vertical mounting means synoptic diagram of detector;

Fig. 4 is pseudo-dual intensity χ ray machine and detector mounting means synoptic diagram;

Fig. 5 is two monoenergetic χ ray machines and the horizontal mounting means synoptic diagram of detector;

Fig. 6 is monoenergetic X-ray machine and pseudo-dual intensity detector mounting means synoptic diagram (two groups detector also can in other position, as on same xsect).

Among the figure: the 1-measuring equipment; The target spot of 2-high energy χ ray machine; The collimating apparatus and the screened room of 3-high energy χ ray machine; 4-(first group) detector; The shielded-plate tube of 5-(first group) detector; The target spot of 6-low energy χ ray machine; The collimating apparatus and the screened room of 7-low energy χ ray machine; Second group of detector of 8-; The shielded-plate tube of second group of detector of 9-; The 10-crude oil pipeline; 12-power spectrum pre-hardening device; The 13-rotating mechanism; 20-(first via) signal shaping, amplification and sample holding unit; 21-the second road signal shaping, amplification and sample holding unit; The high-voltage power supply of 22-(first group) detector; The high-voltage power supply of second group of detector of 23-; 24-(first via) AD converting unit; 25-the second road AD converting unit; 26-(first via) control module; 27-the second road control module; The 28-computing machine; The control system of the true dual intensity χ of 30-ray machine; The control system of 31-high energy χ ray machine; The control system of 32-low energy χ ray machine; 33-(first via) gamma correction detector; 34-Third Road signal shaping, amplification and sample holding unit; The high-voltage power supply of 35-Third Road detector; 36-Third Road AD converting unit; 37-Third Road control module; 38-the second road gamma correction detector; 39-the four road signal shaping, amplification and sample holding unit; The high-voltage power supply of 40-the No. four detector; 41-the four road AD converting unit; 42-the four road control module; 50-power spectrum filter.

Embodiment

Technical solution of the present invention realizes as follows:

To monoenergetic gamma rays, follow exponential damping law with the interaction of material, promptly formula (1) is set up.

$N\left(x_m\right)=N_0{e}^{-{\mathrm{\μ}}_m\·x_m}---\left(1\right)$

Wherein: N ₀----after ray passes air, the counting of measurement.

N (x _m) to pass mass thickness be x to----ray _mMaterial after, the counting of measurement.

x _m----ray passes the mass thickness of material.

μ _m----ray passes the mass attenuation coefficient of material.

Because the power spectrum of the χ ray that the χ ray machine produces is continuous, document [3] has provided the power spectrum that several energy χ ray machines produce, as shown in Figure 1.Have continuum the χ ray, whether the interaction of itself and material also follows exponential damping law? to this theory problem research, referring to document [4].

Referring to the document [4] of instructions end citation, the following proposition of having derived:

On [c, d], use ke in the closed interval ^{-α x}The approximate replacement Error f (x) be estimated as follows:

$f\left(x\right)=k{e}^{-\mathrm{\αx}}-\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{k}_i{e}^{-{\mathrm{\α}}_{i}x}---\left(2\right)$

Here, with [c, d] m five equilibrium, branch is

c＝x0＜x1＜…＜xm-1＜xm＝d $(\mathrm{\Δx}=\frac{d-c}{m})$

Have at branch xj place

$f\left(x_j\right)=k{e}^{-\mathrm{\α}{x}_j}-\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{k}_i{e}^{-{\mathrm{\α}}_i{x}_j}=R_j,j=\mathrm{0,1,2},\mathrm{\Λ},m---\left(3\right).$

Note:

R＝max{|R _j| j＝0，1，2，Λ，m}

$G=\max \left\{\begin{array}{cc}\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{k}_i{e}^{-{\mathrm{\α}}_i{x}_j}& j=\mathrm{0,1,2},\mathrm{\Λ},m\end{array}\right\}$

After some derivation, draw:

$\left|f\left(x\right)\right|\≤R+\frac{R}{4}\·{\left(\mathrm{\α\Δx}\right)}^2+\frac{G}{2}{\mathrm{\α}}_{\max }({\mathrm{\α}}_{\max }-{\mathrm{\α}}_{\min }){\left(\mathrm{\Δx}\right)}^2---\left(4\right)$

In the practical application of this problem,

Be equivalent to measured data; Ke ^{-α x}Be equivalent to calculate fitting data; F (x) is equivalent in the corresponding absolute error of x point; R is equivalent to the absolute value of maximum error in all absolute errors; G is equivalent in the measured data maximum; α is equivalent to equivalent mass absorption coefficient μ _mα _iBeing equivalent to ray energy is E _iPairing mass absorption coefficient μ _m(E _i); X is equivalent to the mass thickness x of sample _mΔ x is equivalent to choose the interval delta x of experimental data _m(independent variable).In theory, Δ x can obtain very little, at this moment | f (x) |≤R.R can obtain by contrived experiment, thereby obtains the estimation of error of whole function.If resulting maximum error acceptable words, its attenuation law just can be similar to exponential damping law.

Find that according to the experimental data of theoretical analysis and document [3] under absorber was not too thick situation, interaction with material was approximate follows exponential damping law for it, if too thick, error is just big a bit.To concrete χ ray machine, at first should find out the approximate condition of following exponential damping law with experiment test once.Again according to the maximum ga(u)ge of specimen, determine the minimum energy E of χ ray machine thus _L ^*(corresponding to the pipe high pressure V of low energy χ ray machine _L).Rule of thumb, suggestion foundation $E_H^{*}={2E}_L^{*}$ Determine E _H ^*(corresponding to the pipe high pressure V of high energy χ ray machine _H) value.

Therefore, might as well suppose the χ ray of the χ ray machine discussed, in the thickness range of the specimen that we discussed, the still approximate exponential damping law of following, promptly formula (1) is approximate sets up.For theoretical model and experimental data better meet, special two fitting coefficient k and the c of adding, as shown in Equation (5).

$N\left(x_m\right)=k{N}_0{e}^{-{\mathrm{\μ}}_m\·x_m}+c---\left(5\right)$

Attention:

(1) at this moment in formula (5), should adopt equivalent energy E ^*Notion.

(2) theoretical value of k and c is: k=1; C=0.When lacking experiment value, can directly quote theoretical value.

(3) μ _m(E ^*), k and c, can record by experiment in advance.

(4) in order to write conveniently, below in μ _m(E ^*), all be abbreviated as μ _m

The document listed [2] according to the instructions end, if material is a potpourri, its density is ρ, and linear attenuation coefficient is μ, and the mass attenuation coefficient of contained element is

..., then the mass attenuation coefficient of potpourri calculates with following formula:

$\frac{\mathrm{\μ}}{\mathrm{\ρ}}=\underset{i}{\mathrm{\Σ}}{\left(\frac{\mathrm{\μ}}{\mathrm{\ρ}}\right)}_i{\mathrm{\ω}}_i---\left(6\right)$

ω in the formula ₁, ω ₂..., ω _i..., ω _NBe respectively the percentage by weight of component.

Attention: the mass attenuation coefficient of element is expressed as μ _m, linear thickness is x, mass thickness is x _mThat is:

μ _m＝μ/ρ x _m＝x·ρ

1, considers profit two-phase state (no subscript-crude oil+water admixture, subscript 1-pure water state, the pure crude state of subscript 2-)

μ _m＝ω ₁μ _m1+ω ₂μ _m2

＝ω ₁μ _m1+(1-ω ₁)μ _m2

＝ω ₁(μ _m1-μ _m2)+μ _m2 (7)

Θμ _m＝μ/ρ x _m＝x·ρ

∴ $\mathrm{\μ}\·x={\mathrm{\μ}}_m\·x_m$

$=({\mathrm{\ω}}_1({\mathrm{\μ}}_{m1}-{\mathrm{\μ}}_{m2})+{\mathrm{\μ}}_{m2})\·x_m$

$=({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)$

$=({\mathrm{\ω}}_1({\mathrm{\μ}}_1\frac{\mathrm{\ρ}}{{\mathrm{\ρ}}_1}-{\mathrm{\μ}}_2\frac{\mathrm{\ρ}}{{\mathrm{\ρ}}_2})+{\mathrm{\μ}}_2\frac{\mathrm{\ρ}}{{\mathrm{\ρ}}_2})\·x---\left(8\right)$

(8) substitution (5), and abbreviation gets:

$({\mathrm{\ω}}_1({\mathrm{\μ}}_1\frac{\mathrm{\ρ}}{{\mathrm{\ρ}}_1}-{\mathrm{\μ}}_2\frac{\mathrm{\ρ}}{{\mathrm{\ρ}}_2})+{\mathrm{\μ}}_2\frac{\mathrm{\ρ}}{{\mathrm{\ρ}}_2})\·x=\ln \left(\frac{{\mathrm{kN}}_0}{N\left(x\right)-{\mathrm{kcN}}_0}\right)$

That is:

${\mathrm{\ω}}_1=\frac{\ln \left(\frac{{\mathrm{kN}}_0}{N\left(x\right)-{\mathrm{kcN}}_0}\right)-\left(\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2}\right)\mathrm{x\ρ}}{(\frac{{\mathrm{\μ}}_1}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})\mathrm{x\ρ}}---\left(9\right)$

In this case, unknown quantity water percentage ω ₁, an equation is so adopt a monoenergetic χ ray machine can solve problems of measurement.

2, consider profit gas three-phase state (no subscript-crude oil+water+gas admixture, subscript 1-pure water state, the pure crude state of subscript 2-, subscript 3-pure natural gaseity)

μ _m＝ω ₁μ _m1+ω ₂μ _m2+ω ₃μ _m3

＝ω ₁μ _m1+(1-ω ₁-ω ₃)μ _m2+ω ₃μ _m3

＝ω ₁(μ _m1-μ _m2)+ω ₃(μ _m3-μ _m2)+μ _m2 (10)

Θμ _m＝μ/ρ x _m＝x·ρ

∴ $\mathrm{\μ}\·x={\mathrm{\μ}}_m\·x_m$

$=({\mathrm{\ω}}_1({\mathrm{\μ}}_{m1}-{\mathrm{\μ}}_{m2})+{\mathrm{\ω}}_3({\mathrm{\μ}}_{m3}-{\mathrm{\μ}}_{m2})+{\mathrm{\μ}}_{m2})\·x_m$

$=({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})+{\mathrm{\ω}}_3(\frac{{\mathrm{\μ}}_3}{{\mathrm{\ρ}}_3}-\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)---\left(11\right)$

(11) substitution (5), and abbreviation gets:

$({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})+{\mathrm{\ω}}_3(\frac{{\mathrm{\μ}}_3}{{\mathrm{\ρ}}_3}-\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)\mathrm{\ρ}=\ln \left(\frac{{\mathrm{kN}}_0}{N\left(x\right)-{\mathrm{kcN}}_0}\right)---\left(12\right)$

In order to try to achieve water percentage ω ₁With void fraction ω ₃, need list two equations of similar (12).On nuclear physics, can try to achieve by the χ ray measurement of two kinds of different-energy χ ray machines.

Adopt the dual intensity measurement pattern to be discussed below herein:

If E _H ^*, E _L ^*Represent the high energy and the pairing equivalent energy of low energy χ ray of χ ray machine respectively, then (12) can be expressed as:

$({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1\left(E_H^{*}\right)}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})+{\mathrm{\ω}}_3(\frac{{\mathrm{\μ}}_3\left(E_H^{*}\right)}{{\mathrm{\ρ}}_3}-\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)$

$=\ln \left(\frac{k_H{N}_0\left(E_H^{*}\right)}{N(x,E_H^{*})-k_H{c}_H{N}_0\left(E_H^{*}\right)}\right)---\left(13\right)$

$({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1\left(E_L^{*}\right)}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})+{\mathrm{\ω}}_3(\frac{{\mathrm{\μ}}_3\left(E_L^{*}\right)}{{\mathrm{\ρ}}_3}-\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)$

$=\ln \left(\frac{k_L{N}_0\left(E_L^{*}\right)}{N(x,E_L^{*})-k_L{c}_L{N}_0\left(E_L^{*}\right)}\right)---\left(14\right)$

In theory, can try to achieve ω according to equation (13) and (14) ₁And ω ₃, the dual intensity χ radionetric survey water percentage under Here it is the profit gas three-phase state and the principle of void fraction.

Attention:

1) at experiment measuring ρ ₁, ρ ₂, ρ ₃During with ρ, need the temperature of while test sample, the influence of pressure and other parameters.

2) because the state of gas and temperature, pressure are closely related, in the application, measure and the corresponding to ρ of physical condition ₃And μ _M3

3) during solving equation, utilize look-up table, adopt and the corresponding ρ value of physical condition, can be by measuring in real time.

4) high energy E _H ^*With low energy E _L ^*Difference big more, measuring accuracy is good more.For example: $E_H^{*}\≈(1.5~3)E_L^{*},$ More simply, $E_H^{*}={2E}_L^{*}.$

5) the various coefficients in the formula, μ ₁, μ ₂, μ ₃, k and c etc., can be in the laboratory, use respectively high and low can the χ ray machine, the demarcation medium (pure crude oil, pure water, pure natural gas) of irradiation different quality thickness with the experimental data that the attenuation measurement method obtains, is tried to achieve by least square fitting again.Attention: k and c can be similar to the pairing value of crude oil, also can measure data in the laboratory at various situations, build up a database, when using at the scene, obtain this data with look-up table.Last model (also can adopt other proper model) of deriving according to the present invention is calculated indexs such as water percentage in the crude oil, void fraction.

The invention will be further described below in conjunction with accompanying drawing and concrete embodiment.

Referring to each accompanying drawing, overall design philosophy of the present invention: this measurement mechanism 1 mainly is made up of three big subsystems.The χ ray machine of two kinds of energy constitutes the χ ray and produces subsystem; One or two cover detectors formation detector subsystems; Form with total control and data processing subsystem.Other subsystem part also comprises collimating apparatus, or other mechanism etc.The detector subsystem comprises unit such as detector, prime amplifier or photomultiplier, signal shaping, amplification, sampling maintenance, AD conversion.The transmission of data, synchronously, work such as demonstration, each several part control and warning are finished by total control and data processing subsystem unification.

Number in the figure implication: 1-measuring equipment; The target spot of 2-high energy χ ray machine; The collimating apparatus and the screened room of 3-high energy χ ray machine; 4-(first group) detector; The shielded-plate tube of 5-(first group) detector; The target spot of 6-low energy χ ray machine; The collimating apparatus and the screened room of 7-low energy χ ray machine; Second group of detector of 8-; The shielded-plate tube of second group of detector of 9-; The 10-crude oil pipeline; 12-power spectrum pre-hardening device; The 13-rotating mechanism; 20-(first via) signal shaping, amplification and sample holding unit; 21-the second road signal shaping, amplification and sample holding unit; The high-voltage power supply of 22-(first group) detector; The high-voltage power supply of second group of detector of 23-; 24-(first via) AD converting unit; 25-the second road AD converting unit; 26-(first via) control module; 27-the second road control module; The 28-computing machine; The control system of the true dual intensity χ of 30-ray machine; The control system of 31-high energy χ ray machine; The control system of 32-low energy χ ray machine; 33-(first via) gamma correction detector; 34-Third Road signal shaping, amplification and sample holding unit; The high-voltage power supply of 35-Third Road detector; 36-Third Road AD converting unit; 37-Third Road control module; 38-the second road gamma correction detector; 39-the four road signal shaping, amplification and sample holding unit; The high-voltage power supply of 40-the No. four detector; 41-the four road AD converting unit; 42-the four road control module; 50-power spectrum filter.

According to principle of the present invention, provide following four kinds of application examples:

1, the principle of work of true dual intensity χ ray machine measuring system

The installation site of the core component of measuring equipment 1 as shown in Figure 2.

The feature of true dual intensity χ ray machine is that the position of the target spot 6 of the target spot 2 of high energy χ ray and low energy χ ray overlaps substantially, the alternately output of timesharing of the high and low energy of the control system 30 controls χ ray of true dual intensity χ ray machine, the frequency of output pulse is relevant with the speed of fluid.Wish high and low can beating simultaneously on the same position of medium by the χ ray in theory, in the practice, can be according to uniformity coefficient, the flow velocity of medium, require the interval of Monitoring Data etc., regulate its parameter, to guarantee test condition As soon as possible Promising Policy theoretical model and error requirements.

The χ ray that is sent by target spot 2 and 6 after collimating apparatus 3 and 7 (the two is integrated, for consistent with numbering in other example hereinafter, specially keeps two labels), passes the medium in the crude oil pipeline 10, is detected device 4 and converts electric signal to.The effect of the shielded-plate tube 5 of detector is that protection detector 4 and reducing is surveyed the influence to detector 4 of background, scattered signal.

The high-voltage power supply 22 of detector provides operating voltage for detector 4, the signal of detector 4 outputs to signal shaping, amplification and sample holding unit 20, signal is delivered to AD converting unit 24 and is converted digital signal to through after amplifying, handling, and delivers to computing machine 28 at last and carries out analyzing and processing.Control module 26 is used for synchronously, coordinates the work of each unit or subsystem.

Economized the second cover detector system in this example, high and low can signal identification, be to realize alternately synchronously by the control system 30 of true dual intensity χ ray machine and the signal of control module 26.

If the line of χ ray machine is bigger over time, promptly the line instability then when the actual treatment data, should be revised it.For the line that obtains the χ ray machine is measured over time, need to increase the detection system that is used for gamma correction.That is: in the outlet of χ ray machine one road gamma correction detector 33 is installed, the high-voltage power supply 35 of Third Road detector provides high pressure for detector 33, the signal of detector 33 outputs to Third Road signal shaping, amplification and sample holding unit 34, signal is through after amplifying, handling, deliver to Third Road AD converting unit 36 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.Control module 37 is used for synchronously, coordinates the work of each unit or subsystem.

If the line of χ ray machine is stable, to the error that systematic survey brings, can ignore, then the detection system of relevant gamma correction can be omitted.

Special software on the computing machine 28, earlier the data that detect are divided into high energy group DS and low energy group DS, use the high and low energy data that brightness detector obtains, respectively its corresponding all data are constantly revised, at first eliminated the line influence over time of χ ray machine.Then, use the model (also can adopt other proper model) of deriving among the present invention, calculate indexs such as water percentage in the crude oil, void fraction.

2, the principle of work of two monoenergetic χ ray machines and the vertical mounting means measuring system of detector

The installation site of the core component of measuring equipment 1 as shown in Figure 3.

Should be that utilizing at present, existing two monoenergetic χ ray machines produce high and low energy χ ray with the characteristics of example.The target spot 2 of high energy χ ray, collimating apparatus 3, detector 4 and shielded-plate tube 5 etc. are formed a cover high energy χ X-ray detection X path, and in like manner the target spot 6 of low energy χ ray, collimating apparatus 7, detector 8 and shielded-plate tube 9 etc. are formed a cover low energy χ X-ray detection X path.Two covers survey paths the closer to, can satisfy more and wish that in theory high low energy χ ray can play the same locational desirable requirement at medium simultaneously.In the practice, can be according to uniformity coefficient, the flow velocity of medium, require the interval of Monitoring Data etc., regulate its parameter, to guarantee test condition As soon as possible Promising Policy theoretical model and error requirements.

The target spot 2 of the control system 31 control high energy χ ray machines of high energy χ ray machine sends high energy χ ray, behind collimating apparatus and screened room 3, passes the medium in the crude oil pipeline 10, is converted to electric signal by first group of detector 4.The effect of the shielded-plate tube 5 of first group of detector is first group of detector 4 of protection, reduces the influence to first group of detector 4 of background, scattered signal simultaneously.The high-voltage power supply 22 of first group of detector provides operating voltage for first group of detector 4, the signal of first group of detector 4 outputs to first via signal shaping, amplification and sample holding unit 20, signal is through after amplifying, handling, deliver to first via AD converting unit 24 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.First via control module 26 is used for synchronously, coordinates the work of each unit of the first via and relative subsystem.

In like manner the target spot 6 of the control system 32 control low energy χ ray machines of low energy χ ray machine sends low energy χ ray, behind collimating apparatus and screened room 7, passes the medium in the crude oil pipeline 10, is converted to electric signal by second group of detector 8.The effect of the shielded-plate tube 9 of second group of detector is second group of detector 8 of protection, reduces the influence to second group of detector 8 of background, scattered signal simultaneously.The high-voltage power supply 23 of second group of detector provides operating voltage for second group of detector 8, the signal of second group of detector 8 outputs to the second road signal shaping, amplification and sample holding unit 21, signal is through after amplifying, handling, deliver to the second road AD converting unit 25 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.The second road control module 27 is used for synchronously, coordinates the work of the second road each unit and relative subsystem.

In this example, reduced designing requirement, as long as use product in the market to the χ ray machine.High and low signal on the same position can come synchronous in addition with the speed and the detection time of fluid.

If the line of χ ray machine is bigger over time, during the actual treatment data, should revise it.For the line that obtains high energy χ ray machine is measured over time, need to increase the detection system that is used for gamma correction.That is: in the outlet of high energy χ ray machine first via gamma correction detector 33 is installed, the high-voltage power supply 35 of Third Road detector provides high pressure for detector 33, the signal of detector 33 outputs to Third Road signal shaping, amplification and sample holding unit 34, signal is through after amplifying, handling, deliver to Third Road AD converting unit 36 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.Control module 37 is used for synchronously, coordinates the work of each unit or subsystem.

In like manner, for the line that obtains low energy χ ray machine is measured over time, in the outlet of low energy χ ray machine the second road gamma correction detector 38 is installed, the high-voltage power supply 40 of the No. four detector provides high pressure for detector 38, the signal of detector 38 outputs to the four road signal shaping, amplification and sample holding unit 39, signal is delivered to the four road AD converting unit 41 and is converted digital signal to through after amplifying, handling, and delivers to computing machine 28 at last and carries out analyzing and processing.The four road control module 42 is used for synchronously, coordinates the work of each unit or subsystem.

If the line of χ ray machine is stable, to the error that systematic survey brings, can ignore, then the detection system of relevant gamma correction can be omitted.

Special software on the computing machine 28, earlier detecting high energy group data and low energy group data, use the high and low energy data that brightness detector obtains, respectively its corresponding all data are constantly revised, at first eliminate the line influence over time of χ ray machine.Then, use the model (also can adopt other proper model) of deriving among the present invention, calculate indexs such as water percentage in the crude oil, void fraction.

3, the principle of work of pseudo-dual intensity χ ray machine measuring system

The installation site of the core component of measuring equipment 1 as shown in Figure 4.

Should be that utilizing at present, an existing monoenergetic χ ray machine produces high and low energy χ ray by timesharing pre-hardening technology with the characteristics of example.The target spot 2 of χ ray machine, collimating apparatus 3, detector 4 and shielded-plate tube 5 are formed a cover χ X-ray detection X path.Power spectrum pre-hardening device 12 is installed together with rotating mechanism 13, and the rotation center of rotating mechanism 13 can not block the target spot 2 of χ ray machine.When the position of rotating mechanism 13 rotation made power spectrum pre-hardening device 12 block the χ ray that target spot 2 sends, at this moment the χ ray that shoots out from collimating apparatus 3 was exactly a high energy χ ray, and the high energy measuring system is used as by system.Otherwise system is used as the low energy measuring system and uses.In the practice, can be according to uniformity coefficient, the flow velocity of medium, require the interval of Monitoring Data etc., regulate rotating mechanism 13 rotational speeies, to guarantee test condition As soon as possible Promising Policy theoretical model and error requirements.

χ ray by target spot 2 sends through after the collimating apparatus 3, passes the medium in the crude oil pipeline 10, is detected device 4 and converts electric signal to.The effect of the shielded-plate tube 5 of detector is a protection detector 4, reduce to survey the influence to detector 4 of background, scattered signal simultaneously.The high-voltage power supply 22 of detector provides operating voltage for detector 4, the signal of detector 4 outputs to signal shaping, amplification and sample holding unit 20, signal is delivered to AD converting unit 24 and is converted digital signal to through after amplifying, handling, and delivers to computing machine 28 at last and carries out analyzing and processing.The identification that control module 26 was used for synchronously, coordinated the work, particularly high and low energy of each unit or subsystem is to realize alternately by the control system 30 of χ ray machine and the signal of control module 26.

In this example, reduced designing requirement, as long as use product in the market to the χ ray machine.

If the line of χ ray machine is bigger over time, during the actual treatment data, should revise it.For the line that obtains the χ ray machine is measured over time, need to increase the detection system that is used for gamma correction.That is: in the outlet of χ ray machine one road gamma correction detector 33 is installed, the high-voltage power supply 35 of Third Road detector provides high pressure for detector 33, the signal of detector 33 outputs to Third Road signal shaping, amplification and sample holding unit 34, signal is through after amplifying, handling, deliver to Third Road AD converting unit 36 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.Control module 37 is used for synchronously, coordinates the work of each unit or subsystem.

If the line of χ ray machine is stable, to the error that systematic survey brings, can ignore, then the detection system of relevant gamma correction can be omitted.

Special software on the computing machine 28, earlier the data that detect are divided into high energy group DS and low energy group DS, use the high and low energy data that brightness detector obtains, respectively its corresponding all data are constantly revised, at first eliminated the line influence over time of χ ray machine.Then, use the model (also can adopt other proper model) of deriving among the present invention, calculate indexs such as water percentage in the crude oil, void fraction.

4, the principle of work of two monoenergetic χ ray machines and the horizontal mounting means measuring system of detector

The installation site of the core component of measuring equipment 1 as shown in Figure 5.

Should be that utilizing at present, existing two monoenergetic χ ray machines produce high and low energy χ ray with the characteristics of example.The target spot 2 of high energy χ ray machine, collimating apparatus 3, detector 4 and shielded-plate tube 5 are formed a cover high energy χ X-ray detection X path, and in like manner the target spot 6 of low energy χ ray machine, collimating apparatus 7, detector 8 and shielded-plate tube 9 are formed a cover low energy χ X-ray detection X path.Two covers are surveyed path on the same xsect of crude oil pipeline 10, have reduced the length of measuring equipment 1 like this.The angle of noting two cover detection paths shown in Fig. 5 not necessarily requires 90 °, as long as can the complete test component that installs.This example requires fluid approximate identical in the same cross-sectional distribution of crude oil pipeline 10, could satisfy like this and wish that in theory high low energy χ ray can play the same locational desirable requirement at medium simultaneously.In the practical application, can be before medium flow into testing apparatus, the convection cell of taking measures is stirred, and makes it to mix to get final product.

The target spot 2 of the control system 31 control high energy χ ray machines of high energy χ ray machine sends high energy χ ray, behind collimating apparatus and screened room 3, passes the medium in the crude oil pipeline 10, is converted to electric signal by first group of detector 4.The effect of the shielded-plate tube 5 of first group of detector is first group of detector 4 of protection, reduces the influence to first group of detector 4 of background, scattered signal simultaneously.The high-voltage power supply 22 of first group of detector provides operating voltage for first group of detector 4, the signal of first group of detector 4 outputs to first via signal shaping, amplification and sample holding unit 20, signal is through after amplifying, handling, deliver to first via AD converting unit 24 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.First via control module 26 is used for synchronously, coordinates the work of each unit of the first via and relative subsystem.

In like manner the target spot 6 of the control system 32 control low energy χ ray machines of low energy χ ray machine sends low energy χ ray, behind collimating apparatus and screened room 7, passes the medium in the crude oil pipeline 10, is converted to electric signal by second group of detector 8.The effect of the shielded-plate tube 9 of second group of detector is second group of detector 8 of protection, reduces the influence to second group of detector 8 of background, scattered signal simultaneously.The high-voltage power supply 23 of second group of detector provides operating voltage for second group of detector 8, the signal of second group of detector 8 outputs to the second road signal shaping, amplification and sample holding unit 21, signal is through after amplifying, handling, deliver to the second road AD converting unit 25 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.The second road control module 27 is used for synchronously, coordinates the work of the second road each unit and relative subsystem.

In this example, reduced designing requirement, as long as use product in the market to the χ ray machine.The measure that can adopt fluid-mixing of the high and low signal on the same position keeps evenly the xsect of fluid, with the condition of this approximation theory model.

If the line of χ ray machine is bigger over time, during the actual treatment data, should revise it.For the line that obtains high energy χ ray machine is measured over time, need to increase the detection system that is used for gamma correction.That is: in the outlet of high energy χ ray machine first via gamma correction detector 33 is installed, the high-voltage power supply 35 of Third Road detector provides high pressure for detector 33, the signal of detector 33 outputs to Third Road signal shaping, amplification and sample holding unit 34, signal is through after amplifying, handling, deliver to Third Road AD converting unit 36 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.Control module 37 is used for synchronously, coordinates the work of each unit or subsystem.

In like manner, for the line that obtains low energy χ ray machine is measured over time, in the outlet of low energy χ ray machine the second road gamma correction detector 38 is installed, the high-voltage power supply 40 of the No. four detector provides high pressure for detector 38, the signal of detector 38 outputs to the four road signal shaping, amplification and sample holding unit 39, signal is delivered to the four road AD converting unit 41 and is converted digital signal to through after amplifying, handling, and delivers to computing machine 28 at last and carries out analyzing and processing.The four road control module 42 is used for synchronously, coordinates the work of each unit or subsystem.

If the line of χ ray machine is stable, to the error that systematic survey brings, can ignore, then the detection system of relevant gamma correction can be omitted.

Special software on the computing machine 28, earlier the high energy group DS and the low energy group DS that detect, use the high and low energy data that brightness detector obtains, respectively its corresponding all data are constantly revised, at first eliminate the line influence over time of χ ray machine.Then, use the model (also can adopt other proper model) of deriving among the present invention, calculate indexs such as water percentage in the crude oil, void fraction.

5, monoenergetic X-ray machine and pseudo-dual intensity detector mounting means

The installation site of the core component of measuring equipment 1 as shown in Figure 6.Attention: No. two detectors also can be installed in other position, as on crude oil pipeline 10 same xsects.

Should be with the characteristics of example, utilize an existing monoenergetic χ ray machine at present, by adopting the pre-hardening technology to produce high energy χ X-ray detection X path to No. one detector, another road detector then be a low energy χ X-ray detection X path.Power spectrum filter 50 is installed in the front of detector 4, and the target spot 2 of χ ray machine, collimating apparatus 3, power spectrum filter 50, detector 4 and shielded-plate tube 5 are formed a cover high energy χ X-ray detection X path.At this moment the high energy measuring system is used as by this road system.The shielded-plate tube 9 of the target spot 2 of χ ray machine, collimating apparatus 3, second group of detector 8 and second group of detector is formed another set of low energy χ X-ray detection X path, and this road system is used as the low energy measuring system and uses.

The first via: the χ ray by target spot 2 sends, through after the collimating apparatus 3, pass the medium in the crude oil pipeline 10, after the power spectrum pre-hardening, become the high energy power spectrum through power spectrum filter 50, be detected device 4 and convert electric signal to.The effect of the shielded-plate tube 5 of detector is a protection detector 4, reduce to survey the influence to detector 4 of background, scattered signal simultaneously.The high-voltage power supply 22 of detector provides operating voltage for detector 4, the signal of detector 4 outputs to signal shaping, amplification and sample holding unit 20, signal is delivered to AD converting unit 24 and is converted digital signal to through after amplifying, handling, and delivers to computing machine 28 at last and carries out analyzing and processing.Control module 26 is used for synchronously, coordinates the work of each unit or subsystem.

The second the tunnel: the χ ray by target spot 2 sends, through after the collimating apparatus 3, pass the medium in the crude oil pipeline 10, converted to electric signal by second group of detector 8.The effect of the shielded-plate tube 9 of second group of detector is a protection detector 8, reduce to survey the influence to detector 8 of background, scattered signal simultaneously.The high-voltage power supply 23 of second group of detector provides operating voltage for detector 8, the signal of detector 8 outputs to the second road signal shaping, amplification and sample holding unit 21, signal is through after amplifying, handling, deliver to the second road AD converting unit 25 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.The second road control module 27 is used for synchronously, coordinates the work of each unit or subsystem.

In this example, reduced designing requirement, as long as use product in the market to the χ ray machine.

If the line of χ ray machine is bigger over time, during the actual treatment data, should revise it.For the line that obtains the χ ray machine is measured over time, need to increase the detection system that is used for gamma correction.That is: in the outlet of χ ray machine one road gamma correction detector 33 is installed, the high-voltage power supply 35 of Third Road detector provides high pressure for detector 33, the signal of detector 33 outputs to Third Road signal shaping, amplification and sample holding unit 34, signal is through after amplifying, handling, deliver to Third Road AD converting unit 36 and convert digital signal to, deliver to computing machine 28 at last and carry out analyzing and processing.Control module 37 is used for synchronously, coordinates the work of each unit or subsystem.

If the line of χ ray machine is stable, to the error that systematic survey brings, can ignore, then the detection system of relevant gamma correction can be omitted.

Special software on the computing machine 28, earlier the data that detect are divided into high energy group DS and low energy group DS, use the high and low energy data that brightness detector obtains, respectively its corresponding all data are constantly revised, at first eliminated the line influence over time of χ ray machine.Then, use the model (also can adopt other proper model) of deriving among the present invention, calculate indexs such as water percentage in the crude oil, void fraction.

List of references:

[1] Ren Xiaofeng, Li Jian etc., " principle and the application of ray volume type crude oil gassiness, instrument for analyzing water content ", instrument and meter for automation, Vol.28, No.10,2007.

[2] Li Xinghong, " radiation protection basis ", Atomic Energy Press, nineteen eighty-two.

[3] He Chengfa, Ba Weizhen, my duty etc., " the attenuation measurement method is determined the X-ray machine power spectrum ", the 9th national nuclear electronics and the academic nd Annual Meeting collection of nuclear detection technology, 1998 years.

[4] Luoping peace, Miu Weidong, Zhu Zhongmei etc., " Beta-ray absorbing rule research ", Beijing nuclear association ' 99 young nuclear technical paper public lecture collected works, 1999.(Luo?Pingan，Miao?Weidong，Zhu?Zhongmei?etc.“The?Research?on?β?Rays?AbsorbingLaw”，’99?Youth?Nuclear?Technological?Conference?ofthe?Beijing?Nuclear?Academy，1999.)

Claims (10)

1. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil, χ ray and material action principle that system utilizes the χ ray machine to produce, in field produces, under the profit gas three-phase medium and the condition of depositing, measure water percentage and void fraction index in the oil pipeline, it is characterized in that: this measuring method relies on a measuring equipment (1) and a cover special software of mainly being made up of three big subsystems, that is: the generation subsystem of two kinds of energy χ rays, the detector subsystem that one or two cover detectors constitute, and master control and data processing subsystem are formed; Other device also comprises collimating apparatus; Described detector subsystem comprises unit such as detector, prime amplifier or photomultiplier, signal shaping, amplification, sampling maintenance, AD conversion; Total control and data processing subsystem comprise the transmission of data, synchronously, parts such as demonstration, control and warning; Adopted special algorithm to find the solution water percentage ω in the described special software ₁With void fraction ω ₃ω ₁The shared percentage by weight of expression water is a water percentage, ω ₃The shared percentage by weight of expression rock gas is a void fraction, ω ₂The percentage by weight ω that expression oil is shared ₂=1-ω ₁-ω ₃

2. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1 is characterized in that: under profit gas three-phase state, this software has adopted two following equations to find the solution water percentage ω ₁With void fraction ω ₃,

$({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1\left(E_H^{*}\right)}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})+{\mathrm{\ω}}_3(\frac{{\mathrm{\μ}}_3\left(E_H^{*}\right)}{{\mathrm{\ρ}}_3}-\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2\left(E_H^{*}\right)}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)$

$=\ln \left(\frac{k_H{N}_0\left(E_H^{*}\right)}{N(x,E_H^{*})-k_H{c}_H{N}_0\left(E_H^{*}\right)}\right)---\left(13\right)$

$({\mathrm{\ω}}_1(\frac{{\mathrm{\μ}}_1\left(E_L^{*}\right)}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})+{\mathrm{\ω}}_3(\frac{{\mathrm{\μ}}_3\left(E_L^{*}\right)}{{\mathrm{\ρ}}_3}-\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})+\frac{{\mathrm{\μ}}_2\left(E_L^{*}\right)}{{\mathrm{\ρ}}_2})\·\left(\mathrm{x\ρ}\right)$

$=\ln \left(\frac{k_L{N}_0\left(E_L^{*}\right)}{N(x,E_L^{*})-k_L{c}_L{N}_0\left(E_L^{*}\right)}\right)---\left(14\right)$

In the above-mentioned equation: E _H ^*, E _L ^*Represent the high energy and the pairing equivalent energy of low energy χ ray of χ ray machine respectively; ρ represents the actual density under the profit gas three-phase state in the oil pipe, ρ ₁Represent in the actual oil pipe density of pure water under the conditions such as pairing temperature, pressure, ρ ₂Represent in the actual oil pipe density of pure crude oil under the conditions such as pairing temperature, pressure, ρ ₃Represent in the actual oil pipe density of pure natural gas under the conditions such as pairing temperature, pressure; μ ₁, μ ₂, μ ₃Represent pure water, pure crude oil, the linear attenuation coefficient of pure natural gas under the equivalent ray energy of correspondence respectively; X represents in the oil pipe, the linear thickness of test macro measurement space; N ₀(E ^*) representative under the equivalent ray energy condition of correspondence, when existing without any material in the oil pipe, the counting that test macro is measured; N ₀(x, E ^*) represent under the measurement thickness of correspondence, equivalent ray energy condition the counting that test macro is measured; K, c are respectively correction factor, same μ ₁, μ ₂, μ ₃Together, can try to achieve by measuring exponential decay curve in advance.

3. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1, it is characterized in that: when only considering profit two-phase state, can be reduced to monoenergetic to the χ ray machine energy of measuring system, adopt following formula to find the solution water percentage ω in the at this moment described software ₁,

${\mathrm{\ω}}_1=\frac{\ln \left(\frac{k{N}_0}{N\left(x\right)-\mathrm{kc}{N}_0}\right)-\left(\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2}\right)\mathrm{x\ρ}}{(\frac{{\mathrm{\μ}}_1}{{\mathrm{\ρ}}_1}-\frac{{\mathrm{\μ}}_2}{{\mathrm{\ρ}}_2})\mathrm{x\ρ}}---\left(9\right)$

In the formula: ρ represents the actual density under the profit two-phase state in the oil pipe, ρ ₁Represent in the actual oil pipe density of pure water under the conditions such as pairing temperature, pressure, ρ ₂Represent in the actual oil pipe density of pure crude oil under the conditions such as pairing temperature, pressure; μ ₁, μ ₂Represent pure water, the linear attenuation coefficient of pure crude oil under the equivalent ray energy of correspondence respectively; X represents in the oil pipe, the linear thickness of test macro measurement space; N ₀Representative under the equivalent ray energy condition of correspondence, when existing without any material in the oil pipe, the counting that test macro is measured; N ₀(x) represent under the measurement thickness of correspondence, equivalent ray energy condition the counting that test macro is measured; K, c are respectively correction factor, same μ ₁, μ ₂Together, can try to achieve by measuring exponential decay curve in advance.

4, the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1 is characterized in that: during design χ optical-mechanical system, the certain condition that satisfies between the high and low energy should be taken into account high energy E _H ^*With low energy E _L ^*Difference big more, measuring accuracy is high more; For example: $E_H^{*}\≈(1.5~3)E_L^{*},$ More simply, $E_H^{*}={2E}_L^{*};$ The energy range of described high energy χ ray machine can be taken between 10keV～1MeV.

5. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1, it is characterized in that: this measuring method relies on true dual intensity χ ray machine measuring system, the mounting means of its measuring equipment (1) core component, be to produce subsystem at the horizontal diameter one end installing χ of crude oil pipeline (10) ray, comprise true dual intensity χ ray machine control system (30), connect collimating apparatus (3) and collimating apparatus (7), be provided with the target spot (2) of the high energy χ ray that the position overlaps substantially and the target spot (6) of low energy χ ray in the collimating apparatus screened room; The other end installing detector subsystem of crude oil pipeline (10) horizontal diameter, comprise detector (4) and shielded-plate tube (5), connect master control and data processing subsystem, comprise high-voltage power supply (22), first via AD converting unit (24), first via control module (26) and the data handling machine (28) of interconnective first via signal shaping, amplification and sample holding unit (20), first group of detector.

6. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1, it is characterized in that: this measuring method relies on two monoenergetic χ ray machines and produces high low energy χ ray, the mounting means of its measuring equipment (1) core component, be by the control system (31) of the high energy χ ray machine of parallel arranged and the control system (32) of low energy χ ray machine, the target spot (2) and high energy χ ray machine collimating apparatus and the screened room (3) that connect high energy χ ray machine respectively, and the collimating apparatus of low energy χ ray machine target spot (6) and low energy χ ray machine and screened room (7), described two monoenergetic χ ray machines, difference corresponding two groups of detector subsystems---first group of detector (4) and shielded-plate tube (5), second group of detector (8) and shielded-plate tube (9), form two parallel detections along separate routes, two groups of detector subsystems connect master control and data processing subsystem separately respectively, that is: one group connects first via signal shaping, amplify and sample holding unit (20), the high-voltage power supply of first group of detector (22), first via AD converting unit (24), first via control module (26), another group connects the second road signal shaping, amplify and sample holding unit (21), the high-voltage power supply of second group of detector (23), the second road AD converting unit (25), the second road control module (27); Two groups of data reach data handling machine (28) respectively.

7. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1, it is characterized in that: this measuring method relies on pseudo-dual intensity χ ray machine measuring system, the mounting means of its measuring equipment (1) core component, comprise a monoenergetic χ ray machine control system (30), corresponding rotation mechanism (13), the same rotating mechanism of power spectrum pre-hardening device (12) (13) is installed together, outer cover collimating apparatus (3), corresponding with it first group of detector (4) and the shielded-plate tube (5) installed; The target spot of χ ray machine (2), collimating apparatus (3), detector (4) and shielded-plate tube (5) are formed a cover χ X-ray detection X path, connect high-voltage power supply (22), first via AD converting unit (24), first via control module (26) and the data handling machine (28) of first via signal shaping, amplification and sample holding unit (20), first group of detector.

8. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1, it is characterized in that: this measuring method relies on two monoenergetic χ ray machine measuring systems, the mounting means of its measuring equipment (1) core component, adopted the horizontal mounting means of two monoenergetic χ ray machines and detector, be to install at four end points positions up and down of crude oil pipeline (10), load the control system (31) of high energy χ ray machine and the control system (32) of low energy χ ray machine respectively at its left end and lower end, be combined with the target spot (2) of high energy χ ray machine respectively, the collimating apparatus of high energy χ ray machine and screened room (3), and the collimating apparatus of the target spot (6) of low energy χ ray machine and low energy χ ray machine and screened room (7), the target spot (2) of high energy χ ray machine, collimating apparatus (3), form a cover high energy χ X-ray detection X path, the target spot of low energy χ ray machine (6) with detector (4) and shielded-plate tube (5) that crude oil pipeline (10) right-hand member is installed, collimating apparatus (7) is formed a cover low energy χ X-ray detection X path with detector (8) and shielded-plate tube (9) that crude oil pipeline (10) right-hand member is installed; Two covers are surveyed path and are on the same xsect of crude oil pipeline (10), to reduce the length of measuring equipment (1); The angles that two covers are surveyed paths can change, and perfect condition is, angle is the smaller the better, and when homogeneity was relatively good on crude oil pipeline (10) xsect, its angle can be greatly.

9. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1, it is characterized in that: this measuring method relies on pseudo-dual intensity detector, the mounting means of its measuring equipment (1) core component, comprise a monoenergetic χ ray machine control system (30), outer cover collimating apparatus (3), corresponding with it power spectrum filter (50), first group of detector (4) and the shielded-plate tube (5) installed in the detector front; The target spot of χ ray machine (2), collimating apparatus (3), power spectrum filter (50), detector (4) and shielded-plate tube (5) are formed a cover high energy χ X-ray detection X path, connect high-voltage power supply (22), first via AD converting unit (24), first via control module (26) and the data handling machine (28) of first via signal shaping, amplification and sample holding unit (20), first group of detector.The shielded-plate tube (9) of target spot (2), collimating apparatus (3), second group of detector (8) and second group of detector of χ ray machine is formed a cover low energy χ X-ray detection X path simultaneously, connects high-voltage power supply (23), the second road AD converting unit (25), the second road control module (27) and the data handling machine (28) of the second road signal shaping, amplification and sample holding unit (21), second group of detector

10. the dual intensity χ radionetric survey method of void fraction and water percentage in the crude oil according to claim 1, it is characterized in that: if χ ray machine line less stable, for improving measuring accuracy, can add one road gamma correction detector, promptly one road gamma correction detector (33) or (38) are installed in the outlet of each χ ray machine; The gamma correction position of detector flows but had better not block the main beam that is used to measure in the outlet of χ ray machine.With gamma correction detector (33) is that example illustrates its installation relation: the target spot of χ ray machine, collimating apparatus and gamma correction detector (33) are formed a cover χ ray line size detection path, connect high-voltage power supply (35), Third Road AD converting unit (36), Third Road control module (37) and the computing machine (28) of Third Road signal shaping, amplification and sample holding unit (34), Third Road detector.

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